What could possibly persuade women from Germany, Indonesia or Russia to leave peaceful nations for a new life in a pariah 'state' at war with all around and with streets soaked in the blood of its victims?

For Difansa Rachmani, it seems, the answer is health care.

A mother-of-three at the time of her immigration to the so called Islamic State in the summer of 2015 - two months after 'the Caliphate' was declared - she told Sky News she made the journey because she'd been promised surgery.

She said she had also been promised help with her autistic three-year-old who could not walk.

Difansa chose, she said, to "put to one side" the atrocities she knew about from the internet.

Video:British IS recruiter 'stuck in Raqqa'

On her arrival she was indeed treated for her condition. As was her son who was able to walk after the two of them travelled to Mosul to get the best medical attention the Caliphate could offer.

One of a family group of 17 - nine women, five men and three children - who moved en masse to a new life in Raqqa, she said that life for them turned sour when the men folk refused to do military service.

The males are currently under interrogation in Kobane by Kurdish intelligence officials while the rest of the family await their fate in a refugee camp in Ain Issa.

Sisters Nur Kharadhania, 19, and Syarafina Nailah, 21, insist the lure of the Caliphate came from online propaganda. Nur especially had an online relationship with a man and a woman already in Raqqa.

She was promised a "great salary" and told that she would be given a large house for her extended family.

Image:Kurdish fighters from the People's Protection Units (YPG) run across a street in Raqqa

Aged 17, she was groomed - almost certainly by a unit of IS specialists led by Sally Jones, a convert from Kent who is the widow of Junaid Hussain, the Eyad of the Caliphate's digital jihad.

Again, she chose to "only look at the beautiful things" that IS had to offer. Indeed she said that she chose to believe that the murders of Jim Foley and others were black propaganda intended to paint the IS in a bad light.

The family's fortunes turned after the men, they claimed, did not fight - but they kept their house.

The family fled Raqqa 23 days ago - which happens to be when the land assault, by Syrian Democratic Forces backed by warplanes from the coalition, intensified on Raqqa.

The men in Raqqa, all three women agreed, were disgusting and "obsessed with women".

The three claim they were put on a list of single women and said they had to brush off marriage proposals that came from a stranger in the morning who demanded an answer by nightfall.

Video:Is this the end of Islamic State?

The Indonesians were treated with less suspicion by Kurdish intelligence than a group of four others - two Syrians, a Russian and a German who were kept in a secure part of the refugee camp.

'Aisha', a Syrian who married a Moroccan volunteer who came to IS in 2014, was adamant that no foreign immigrants had joined in combat, or the mass murders that have defined the so called Caliphate.

"All the immigrants, when they came to Raqqa, it's not for the purpose of fighting or for war. Many immigrants, especially from European countries, they came because they can't do Islam in that place. It's not for war or going to military camps, they just want to live in a Muslim community."

Her friend 'Fatima' married a German-Turk in Raqqa after being groomed online by him. He lost a leg in an airstrike in Mosul - at a time when the coalition was targeting the leadership of IS.

Many IS leaders have sent, or have attempted to, their families out of harm's way in Raqqa. So the IS wives of Ain Issa are of particular interest to US intelligence agents, who arrived to interrogate some of them just as Sky News had finished speaking with the women.

They will be especially interested in news of Sally Jones. She's reported to be on a coalition "kill list" hunted by the drones who buzz over the skies of Raqqa. Day and night.